Shift-multiplexed microhologram fabrication with photoisomeric chromophores.

Microholographic memory is an attractive storage system for its capability to hold high-density data and for its access time. Using a photochromic chromophore (diarylethene)-doped recording medium can give rise to microholographic memory's durability and contrast. In addition, it is possible to increase the microholographic memory's density by shift-multiplexed recording, since a hologram pit is constructed in a small area. The microhologram was fabricated in the diarylethene-based sample with two counterpropagating focused beams. Also, surface images and cross-sectional images scanned by a confocal microscope indicated that shift-multiplexed recording was achieved in high contrast.